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J/AZh/81/1104       Optical spectrum of Cyg OB2 No. 12        (Klochkova+, 2004)

The optical spectrum of the LBV candidate in the Cyg OB2 association. Klochkova V.G., Chentsov E.L. <Astron. Zh. 81, 1104 (2004)> =2004AZh....81.1104K =2004ARep..48..1005K
ADC_Keywords: Stars, blue; Stars, variable; Equivalent widths; Radial velocities Abstract: We have obtained the first high spectral-resolution (R=15000 and 60000) optical spectra for the extremely luminous star No.12, identified with the IR-source IRAS 20308+4104 in the Cyg OB2 association. We have identified about 200 spectral features at 4552-7939Å, including interstellar NaI, KI and numerous DIBs, which are in the strongest absorptions in the spectrum, along with the HeI, CII, SiII lines. A two-dimensional spectral classification indicates that the star's spectral type is B5±0.5 Ia+. Our analyses of the radial velocities pattern shows the presence of a radial velocity gradient in the stellar atmosphere due to the infall of matter onto the star. The strong H(alpha) emission line displays broad Thompson wings and time-variable core absorption, providing evidence that the stellar wind is inhomogeneous and slightly blue-shifted P Cygni absorption profile. We conclude that the wind is time-variable. Objects: ------------------------------------------------- RA (2000) DE Designation(s) ------------------------------------------------- 20 32 40.9 +41 14 29 VI CYG 12 = HIP 101364 ------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 65 202 Line identifications, equivalent widths, residual intensities, and heliocentric radial velocities for the spectra of Cyg OB2-No.12
Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 6 A6 --- El Element (1) 8- 14 A7 --- Mult ? Multiplet number 17- 23 F7.2 0.1nm Lambda Wavelength expressed in Angstroem 24 A1 --- u_Lambda [:] Uncertainty flag on Lambda 27- 30 F4.2 0.1nm EW1 ? Equivalent width for June 12, 2001 31 A1 --- u_EW1 [:] Uncertainty flag on EW1 32 A1 --- n_EW1 [*] *: triplets combined equivalent width 34- 37 F4.2 --- r1 ? Residual intensity for June 12, 2001 38 A1 --- u_r1 [:] Uncertainty flag on Lambda 41- 43 I3 km/s HRV1 ? Heliocentric radial velocity for June 12, 2001 44 A1 --- u_HRV1 [:] Uncertainty flag on HRV1 48- 51 F4.2 0.1nm EW2 ? Equivalent width for April 12, 2003 52 A1 --- u_EW2 [:] Uncertainty flag on EW2 55- 58 F4.2 --- r2 ? Residual intensity for April 12, 2003 59 A1 --- u_r2 [:] Uncertainty flag on Lambda 62- 64 I3 km/s HRV2 ? Heliocentric radial velocity for April 12, 2003 65 A1 --- u_HRV2 [:] Uncertainty flag on HRV2
Note (1): DIB = extremely strong diffuse interstellar band

(End) Veta Avedisova [INASAN] 06-Apr-2006
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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